<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="https://cdn.staticfile.net/font-awesome/4.7.0/css/font-awesome.css">
    <title>Document</title>
    <style>
        body{
            background: red;
            font-family: 'Open Sans', sans-serif;
        }
        .search{
            width: 100%;
            position: relative;
            display: flex;
        }
        .searchterm{
            width: 100%;
            border: 3px solid #00b4cc;
            border-radius: none;
            padding: 5px;
            height: 20px;
            border-radius: 5px 0 0 5px;
            outline: none;
            color: #9dbfaf;
        }
        .searchterm:focus{
            color: #00b4cc;
        }
        .searchbutton{
            width: 40px;
            height: 36px;
            border: 1px solid #00b4cc;
            background: #00b4cc;
            text-align: center;
            color: #fff;
            border-radius: 0 5px 5px 0;
            cursor: pointer;
            font-size: 20px;
        }
        .wrap{
            width: 30%;
            position: absolute;
            top:50%;
            left: 50%;
            transform: translate(-50%,-50%);
        }

    </style>
</head>
<body>
    <h2>搜索框 - 带按钮</h2>
    <div class="wrap">
        <div class="search">
            <input type="text" class="searchterm" placeholder="你想找什么">
            <button type="submit" class="searchbutton">
                <i class="fa fa-search"></i>
            </button>
        </div>
    </div>
    
</body>
</html>